In a 45-year-old woman with episodic intense paraspinal dorsal‑lumbar pain occurring 2–3 times daily for about an hour, normal complete blood count, liver and renal panels, urine studies, chest X‑ray, abdominal ultrasound, and only mildly elevated C‑reactive protein, no fever, tenderness, morning stiffness, nocturnal pain, peripheral joint involvement, or stress, could this be a functional (somatic‑symptom) pain disorder?

Episodic Paraspinal Pain Without Inflammatory Features: Diagnostic Approach

Direct Answer

This presentation does not fit an inflammatory or infectious spinal disorder and warrants consideration of functional somatic pain disorder, particularly given the episodic nature, complete absence of symptoms between episodes, normal examination, and lack of classic inflammatory features.

Why This Is Not Inflammatory Spondyloarthropathy

The clinical picture argues strongly against axial spondyloarthritis (axSpA):

• Inflammatory back pain requires specific features: insidious onset, improvement with exercise (not rest), pain at night, morning stiffness >30 minutes, and age of onset <40-45 years 1, 2
• Your patient lacks all cardinal inflammatory features: no morning stiffness, no nocturnal pain awakening from sleep, pain unrelated to activity or rest, and complete symptom-free intervals 1
• The episodic pattern is atypical: inflammatory conditions cause persistent symptoms with variable intensity, not discrete 1-hour episodes with complete resolution 1
• Normal acute phase reactants argue against active inflammation: while a CRP of 36 mg/L is mildly elevated, it is insufficient to explain significant inflammatory disease, and the patient became asymptomatic despite this elevation 1, 3

Why This Is Not Infectious

Spinal infections present with distinct features absent in your patient:

• Persistent, progressive pain: vertebral osteomyelitis and discitis cause constant pain that worsens over time, not intermittent episodes 1, 4
• Constitutional symptoms: fever (documented, not subjective), elevated inflammatory markers (ESR typically >50-100), and systemic illness 1, 4
• Point tenderness: vertebral body tenderness on palpation is characteristic of infection 4
• Your patient's complete recovery after 2 days and intermittent pain pattern are incompatible with infection 1

Functional Somatic Pain Disorder: The Most Likely Diagnosis

The presentation strongly suggests functional somatic symptoms:

• Medically unexplained pain lasting >6 months with significant impairment meets criteria for functional somatic disorder 5
• Episodic intense pain with complete symptom-free intervals is characteristic of functional pain rather than structural pathology 6, 5
• Normal examination and investigations despite significant subjective symptoms is a hallmark feature 5, 7
• Approximately 10% of the general population and one-third of clinical populations suffer from functional somatic symptoms 5

Key Diagnostic Features Supporting Functional Disorder

• Disproportionate pain to any identifiable pathology: the intensity and pattern don't match any anatomic or physiologic process 6, 7
• Non-anatomic distribution: paraspinal pain that is "absolutely unrelated to exertion or rest" defies biomechanical principles 6
• Fluctuating course with complete resolution: structural or inflammatory conditions don't produce 1-hour episodes with complete recovery 5, 8

Critical Next Steps

Avoid Diagnostic Pitfalls

• Do not pursue extensive imaging or invasive procedures: this reinforces illness behavior and can lead to iatrogenic complications 5, 7
• Do not prescribe opioids: functional pain disorders respond poorly to passive treatments and risk medication dependence 6, 5
• Avoid repeated laboratory testing: this perpetuates the search for organic pathology that doesn't exist 5, 7

Recommended Management Approach

Provide empathetic reassurance with a biopsychosocial explanation:

• Explain that pain is real but not caused by structural damage or inflammation 5
• Frame this as a nervous system processing issue rather than "all in your head" 5
• Emphasize that investigations have ruled out serious pathology 5, 7

Implement active interventions for self-efficacy:

• Physical therapy focused on gradual activation and movement confidence 5
• Cognitive behavioral therapy addressing pain catastrophizing and avoidance behaviors 6, 5
• Encourage return to normal activities despite pain 5

Consider psychiatric comorbidity:

• Depression and anxiety frequently coexist with functional somatic symptoms 5, 8
• Selective serotonin reuptake inhibitors or tricyclic antidepressants may be beneficial 7
• Formal psychiatric assessment may be warranted if symptoms persist 7, 8

When to Reconsider Organic Pathology

Monitor for development of true red flags:

• Progressive neurologic deficits: weakness, sensory loss, or gait disturbance 4
• Documented fever with significantly elevated inflammatory markers (ESR >50, CRP >100) 1, 4
• Constitutional symptoms: weight loss, night sweats, or malaise 1, 4
• Point tenderness on vertebral palpation 4

If any of these develop, obtain MRI spine without contrast to exclude infection, malignancy, or inflammatory disease 3, 4.

Common Pitfall to Avoid

The greatest risk is embarking on an endless diagnostic odyssey that reinforces the patient's belief in serious organic disease, leading to unnecessary procedures, imaging radiation exposure, and potential surgical interventions that will not resolve functional pain 6, 5, 7. The biopsychosocial model with active patient engagement is more effective than passive, organ-focused treatments 5.